Monitoring system

Abstract

The invention relates to a monitoring system ( 10, 20 ) for monitoring of at least a fixed but displaceable object in a volume, which object is provided with at least a marking means ( 13, 13 a - 13 d, 23 ) in form of a light generating or reflecting device, which system at least comprises an optical recording unit ( 11, 21 ) for recording of an image of at least a part of the volume comprising said object provided with the marking means ( 13, 13 a - 13 d, 23 ), device for transformation of said image to a digital representation of the same image, means ( 14 ) for comparison of the digital representation to a stored data-set, and device for generating a signal at the presence of a deviation at comparison of the digital representation to the stored data-set. The data-set stored at least comprises a two-dimensional stationary coordinate value for the initial position of the marking means ( 13, 13 a - 13 d ), that the system comprises means for extracting at least a stationary coordinate value, which is at least a two-dimensional coordinate value, out of the digital representation for the marking means, whereby said comparison means ( 14 ) compares said extracted two dimensional coordinate value to the stored stationary coordinate value.

1 . A monitoring system ( 10 ,  20 ) for monitoring at least one fixed but displaceable object in a volume, which object is provided with at least one marking means ( 13 ,  13   a - 13   d ,  23 ) in form of a light generating or representing device, which system at least comprises an optical recording unit ( 11 ,  21 ) for recording an image of at least a part of the volume comprising said object provided with the marking means ( 13 ,  13   a - 13   d ,  23 ), device for transferring said image to, a digital representation of the same image, means ( 14 ) for comparison of the digital representation to a stored data-set, and device for generating a signal at the presence of a deviation at the comparison of the digital representation with the stored data set,  
       characterized in 
 that the stored data-set at least comprises a two dimensional stationary coordinate value for the initial position of the marking means ( 13 ,  13   a - 13   d ), that the system comprises means for extracting at least a stationary coordinate value, which is at least a two-dimensional coordinate value, out of the digital representation of the marking means, whereby said comparison means ( 14 ) compares said extracted two-dimensional coordinate value with the stored stationary coordinate value.  
 
     
     
         2 . A monitoring system ( 20 ) as claimed in  claim 1 ,  
       characterized in 
 that said object is monitored for uncontrolled displacement.  
 
     
     
         3 . A monitoring system ( 10 ) as claimed in  claim 1  and  2 ,  
       characterized in 
 that the object is provided with a reflecting marker.  
 
     
     
         4 . A monitoring system ( 10 ) as claimed in  claim 2  and  3 ,  
       characterized in 
 that a part of the object is used as marking means.  
 
     
     
         5 . A monitoring system ( 10 ) as claimed in claim  1 - 4 ,  
       characterized in 
 that several marking means are arranged on the same object.  
 
     
     
         6 . A monitoring system ( 20 ) as claimed in  claim 1 ,  
       characterized in 
 that the light intensity of the marking means is also measured.  
 
     
     
         7 . A monitoring system ( 20 ) as claimed in  claim 6 ,  
       characterized in 
 that the stored data set comprises an initial light intensity.  
 
     
     
         8 . A monitoring system ( 20 ) as claimed in  claim 6  or  7 ,  
       characterized in 
 that the system is intended as a fire alarm.  
 
     
     
         9 . A monitoring system ( 20 ) as claimed in any of the preceding claims,  
       characterized in 
 that the system in addition comprises a heat detector.  
 
     
     
         10 . A method for monitoring an object in an volume provided with at least a marking means ( 13 ,  13   a - 13   d ,  23 ) in form of a light generating or reflecting device, whereby the method comprises the steps of: 
 at least arranging one optical sensor unit ( 11 ,  21 ) for recording an image of at least one part of the volume comprising said marking means ( 13 ,  13   a - 13   d ,  23 ),    transforming said image to a digital representation of the same image,    comparing the digital representation to a stored data-set,    characterized in    that the method comprises the steps: 
 at least extracting one coordinate value, which is at least a two-dimensional coordinate value, out of the digital representation of the marking means,  
 comparing said extracted two-dimensional coordinate value to a stored stationary coordinate value for said marking means by means of said comparison means ( 14 ), and  
 generating a signal at the presence of a deviation at comparison of the extracted coordinate value to the stored coordinate value.  
   
     
     
         11 . A method as claimed in  claim 10 ,  
       characterized in 
 that the data comprises a value of the light intensity for said marking means as well.